Autoimmune arthritis, and particularly rheumatoid arthritis, is a painful and often crippling disease that initially results in swollen and inflammed joints, but often progresses to deformed or completely destroyed joints. This is a result of the body mistakenly attacking collagen, which is the major portion of cartilage tissue. Cartilage tissue serves the function of a lubricant in the joints, keeping bone from rubbing on bone. As the disease progresses and more of the cartilage is destroyed, bone does begin to wear on bone. This results in even more severe pain and ultimately destruction of the joint itself. As the disease progresses, the body sometimes attacks other collagen in the soft tissues of the body which can cause a variety of arthritis-related diseases.
In order to initiate the disease, it is apparent that an individual must have an inherent (perhaps genetic) susceptibility. Given this susceptibility, there is now strong evidence that the disease is initiated by exposure to the Epstein-Bart virus. The ability of the Epstein-Bart virus to initiate Rheumatoid Arthritis has been linked to a key amino acid sequence which is identical to a sequence found in human collagen. Thus, in generating antibodies to destroy the Epstein-Bart virus, the body generates antibodies that are also capable of attacking its own collagen. In a similar manner, arthritis has been initiated in rats by the intradermal injection of water-soluble highly purified Type II procollagen extracted from chicken cartilage or by the well known complete Freund Adjuvant.
It was also shown that rats could be prevented from getting arthritis or the effects greatly reduced from this injection of water-soluble highly purified procollagen. This was accomplished by feeding the same water-soluble highly purified procollagen to the rats for several days prior to the injection. It was also shown with rats that, once arthritis had been induced, the effects of the disease could be reduced by the oral administration of the same water-soluble highly purified procollagen. In a later study with humans having severe arthritis it has been shown as disclosed in U.S. Pat. No. 5,399,347 that the oral administration of the water-soluble highly purified procollagen is similarly beneficial to humans in reducing the effects of the disease.
While this oral treatment with water-soluble highly purified procollagen represents a long sought and highly desired treatment for Rheumatoid Arthritis, the required water-soluble highly purified Type II procollagen is very difficult to prepare. Typically, it is extracted from the tiny xiphoid cartilages of 2.5 week old chicks. In a preparation of the past art, eighty animals are required to produce 19 g of cleaned xiphoid cartilage dissected free of surrounding tissue. It is typical of the past art to perform up to seven extractions on each batch of tissue to obtain water-soluble procollagen of the required purity.
The procedure of the past art is thus seen to have several serious deficiencies. An extremely large number of animals are required to obtain a small amount of the desired product. The purification procedure is very time consuming and complicated, requiring breakdown by depolymerization of the molecular structure of the Type II collagen in the cartilage. This is followed by multiple extractions and precipitations. These multiple operations, in addition to being time consuming, difficult, and changing the molecular structure, offer many opportunities for microbiological contamination which would render the water-soluble highly purified procollagen unusable or even dangerous. Often an ultra filtration operation is required to remove contamination from the solubilized product prior to the final precipitation. These complications make the water-soluble highly purified procollagen unavailable to many sufferers of arthritis.